mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    a, b, c = map(int, input().split())

    ok = 10**18
    ng = 0
    mid = (ok+ng)//2
    while ok - ng > 1:
        if mid + (b-1) * (mid // a) >= c:
            ok = mid
        else:
            ng = mid
        mid = (ok+ng)//2
    print(ok)


if __name__ == '__main__':
    main()